Ajax is an acronym for Asynchronous JavaScript and XML that describes a web development technique for enhancing user interactivity and client/server communication in a web application. The term Ajax was first coined in 2005 and since then it has become one of the dominant approaches today for building Rich Internet Applications (RIAs). What Ajax does is allow us to create pages that can update themselves in response to a wide variety of user interactions, creating a more responsive user interface and richer web experience for our users.
Ajax involves JavaScript code that sends asynchronous HTTP requests to the server using the XMLHttpRequest object API supported by modern browsers, then it waits a response from the server, and then it performs changes to the HTML Document Object Model (DOM) to update the web page in the browser (an approach also known as Dynamic HTML or DHTML). When the user clicks on a button, for example, the button invokes a JavaScript function that sends...